Ice rink and method for making ice surface of ice rink

ABSTRACT

The present disclosure discloses a method for making an ice surface of an ice rink and an ice rink including the ice surface. In the method, a salt solution is applied to an ice surface. The salt solution contains anions. A concentration of the anions is in a range from about 0.63 mmol/L to about 10 mmol/L. The anions in the salt solution are selected from the group consisting of chloride ions, nitrate ions, bromide ions, iodide ions, chlorate ions, perchlorate ions, thiocyanate ions, and any combination thereof. The ice surface is maintained at a temperature of about −4° C. to about 14° C. to naturally freeze the salt solution.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority of China Patent Application No. 202111012272X, filed on Aug. 31, 2021, the content of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates to ice rinks, and in particular to an ice rink and a method for making an ice surface of the ice rink.

BACKGROUND

Ice rink based sports, such as speed skating, curling, ice hockey, etc., have drawn increasing attention with promotion and popularity of winter sports. The ice surface of an ice rink is in contact with the athletes or sports equipment, has huge influence on the athletes' experience and performance, and thus has to meet relatively high standards and requirements. Water is sprayed onto the ice rink to make or resurface the ice surface of the ice rink. The actually formed ice surface often has a relatively large and non-uniform coefficient of friction, and even cracks during athletes' skating. These problems not only affect the aesthetics of the ice surface, but also affect the stability of the performance of the athletes, and even become a potential risk factor in some high-speed racing sports.

SUMMARY

Accordingly, the present disclosure provides an ice rink and a method for making an ice surface of the ice rink, which can significantly reduce the friction coefficient of the ice surface and prevent the ice surface from cracking.

In an aspect of the present disclosure, a method for making an ice surface of an ice rink includes following steps:

applying a salt solution to an ice surface, wherein the salt solution contains anions, and a concentration of the anions in the salt solution is in a range from about 0.63 mmol/L to about 10 mmol/L, the anions in the salt solution are selected from the group consisting of chloride ions, nitrate ions, bromide ions, iodide ions, chlorate ions, perchlorate ions, thiocyanate ions, and any combination thereof; and maintaining the ice surface at a temperature of about −4° C. to about 14° C. to naturally freeze the salt solution.

In an embodiment, the temperature of the ice surface is maintained at a temperature of about −6° C. to about −7° C. to naturally freeze the salt solution.

In an embodiment, the anions in the salt solution are chloride ions, and a concentration of the chloride ions is in a range from about 2.5 mmol/L to about 10 mmol/L.

In an embodiment, the anions in the salt solution are nitrate ions, and a concentration of the nitrate ions is in a range from about 2.5 mmol/L to about 8 mmol/L.

In an embodiment, the anions in the salt solution are bromide ions, and a concentration of the bromide ions is in a range from about 2.5 mmol/L to about 6 mmol/L.

In an embodiment, the anions in the salt solution are iodide ions, and a concentration of the iodide ions is in a range from about 2.5 mmol/L to about 5 mmol/L.

In an embodiment, the anions in the salt solution are chlorate ions, and a concentration of the chlorate ions is in a range from about 1 mmol/L to about 5 mmol/L.

In an embodiment, the anions in the salt solution are perchlorate ions, and a concentration of the perchlorate ions is in a range from about 1 mmol/L to about 4 mmol/L.

In an embodiment, the anions in the salt solution are thiocyanate ions, and a concentration of the thiocyanate ions is in a range from about 0.63 mmol/L to about 3 mmol/L.

In another aspect of the present disclosure, an ice rink has an ice surface made by the above-described method for making the ice surface of the ice rink.

In the method for making the ice surface of the ice rink provided in the present disclosure, a salt solution with specific anions and a specific concentration of anions, instead of pure water, is applied to the ice surface for freezing. These anions can form hydrated ions in water. Due to the existence of the hydrated ions, a hydration repulsive force, which is an electrostatic repulsive force, will be generated on the resulting ice surface that is in contact with the sports equipment, thereby reducing the actual contact pressure of the friction pair and thus reducing the friction coefficient of the ice surface. The temperature of the freezing is maintained at about −4° C. to about 14° C. Within this temperature range, the time required for freezing the salt solution will not exceed 30 seconds (sec) due to the low concentration of the salt solution. Therefore, the formed ice crystal has a good morphology, and the friction coefficient of the ice surface will not increase. In addition, the more hydrogen bonds in the structure of the ice, the easier the ice surface is to be destroyed and cracked when it is under pressure. The formation of the hydrated ions destroys the original hydrogen bonds between water molecules. Therefore, the method for making the ice surface of the ice rink provided in the present disclosure can also effectively avoid cracking of the ice surface.

Further, in the method for making the ice surface of the ice rink provided in the present disclosure, the salt solution will not significantly affect other factors of the ice surface, and thus reduces undesired influence, and has a low cost and good practicability.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are described below. Each of the examples is provided by way of illustration but not limitation of the disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the disclosure. For example, features illustrated or described as part of one embodiment can be used in another embodiment to yield a still further embodiment.

Therefore, it is intended that the present disclosure covers such modifications and variations that fall within the scopes of the appended claims and their equivalents. Other objects, features, and aspects of the present disclosure are disclosed in or will be apparent from the following detailed description. It is to be understood by one of ordinary skill in the art that the present discussion is a description of exemplary embodiments only, and is not intended as limiting the broader aspects of the present disclosure.

Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art of the present disclosure. The terms used in the specification of the present disclosure are only intended to describe the purposes of specific embodiments, rather than limiting the present disclosure. The term “and/or” as used herein includes any and all combinations of one or more related listed items.

Unless otherwise indicated, all numbers used in the specification and claims expressing quantities of ingredients, physical and chemical properties, and so on, are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. The disclosure of numerical ranges defined by endpoints herein is an equivalence of a disclosure of all numbers within that range and all sub-ranges within that range. For example, a range of 1 to 5 also discloses any numbers such as 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5 in this range.

An embodiment of the present disclosure provides a method for making an ice surface of an ice rink, including following steps:

apply a salt solution to an ice surface, wherein the salt solution contains anions, and a concentration of the anions in the salt solution is in a range from about 0.63 mmol/L to about 10 mmol/L, the anions in the salt solution are selected from the group consisting of chloride ions, nitrate ions, bromide ions, iodide ions, chlorate ions, perchlorate ions, thiocyanate ions, and any combination thereof; and maintaining the ice surface at a temperature of about −4° C. to about 14° C. to naturally freeze the salt solution.

Cations in the salt solution are not particularly limited, and may include but are not limited to Na⁺, K⁺, Ca²⁺, Fe³⁺, NH₄ ⁺, etc. In some embodiments, the salt solution only includes solvent, anions, and cations, and the anions are only selected from the above mentioned specific anions. In some embodiments, the solvent of the salt solution is only water. In some embodiments, a total concentration of all anions in the salt solution is in a range from about 0.63 mmol/L to about 10 mmol/L.

In some embodiments, the temperature of the ice surface is maintained at a temperature of about −6° C. to about −7° C. Within this temperature range, the salt solution freezes well and the freezing consumes less energy.

In some embodiments, the anions in the salt solution are chloride ions having a concentration that can be any value in a range from about 0.63 mmol/L to about 10 mmol/L, for example, 1.25 mmol/L, 2 mmol/L, 2.5 mmol/L, 3 mmol/L, 3.5 mmol/L, 4 mmol/L, 4.5 mmol/L, 5 mmol/L, 5.5 mmol/L, 6 mmol/L, 6.5 mmol/L, 7 mmol/L, 7.5 mmol/L, 8 mmol/L, 8.5 mmol/L, 9 mmol/L, 9.5 mmol/L, in an embodiment, about 2.5 mmol/L to about 10 mmol/L. The friction coefficient of the ice surface cannot be effectively reduced if the concentration of the chloride ions is too low, and the freezing point of the solution will be lowered if the concentration of the chloride ions is too high, making the solution difficult to freeze.

In some embodiments, the anions in the salt solution are nitrate ions having a concentration that can be any value in a range from about 0.63 mmol/L to about 10 mmol/L, for example, 1.25 mmol/L, 2 mmol/L, 2.5 mmol/L, 3 mmol/L, 3.5 mmol/L, 4 mmol/L, 4.5 mmol/L, 5 mmol/L, 5.5 mmol/L, 6 mmol/L, 6.5 mmol/L, 7 mmol/L, 7.5 mmol/L, 8 mmol/L, 8.5 mmol/L, 9 mmol/L, 9.5 mmol/L, in an embodiment, about 2.5 mmol/L to about 8 mmol/L. The friction coefficient of the ice surface cannot be effectively reduced if the concentration of the nitrate ions is too low, and the freezing point of the solution will be lowered if the concentration of the nitrate ions is too high, making the solution difficult to freeze.

In some embodiments, the anions in the salt solution are bromide ions having a concentration that can be any value in a range from about 0.63 mmol/L to about 10 mmol/L, for example, 1.25 mmol/L, 2 mmol/L, 2.5 mmol/L, 3 mmol/L, 3.5 mmol/L, 4 mmol/L, 4.5 mmol/L, 5 mmol/L, 5.5 mmol/L, 6 mmol/L, 6.5 mmol/L, 7 mmol/L, 7.5 mmol/L, 8 mmol/L, 8.5 mmol/L, 9 mmol/L, 9.5 mmol/L, in an embodiment, about 2.5 mmol/L to about 6 mmol/L. The friction coefficient of the ice surface cannot be effectively reduced if the concentration of the bromide ions is too low, and the freezing point of the solution will be lowered if the concentration of the bromide ions is too high, making the solution difficult to freeze.

In some embodiments, the anions in the salt solution are iodide ions having a concentration that can be any value in a range from about 0.63 mmol/L to about 10 mmol/L, for example, 1.25 mmol/L, 2 mmol/L, 2.5 mmol/L, 3 mmol/L, 3.5 mmol/L, 4 mmol/L, 4.5 mmol/L, 5 mmol/L, 5.5 mmol/L, 6 mmol/L, 6.5 mmol/L, 7 mmol/L, 7.5 mmol/L, 8 mmol/L, 8.5 mmol/L, 9 mmol/L, 9.5 mmol/L, in an embodiment, about 2.5 mmol/L to about 5 mmol/L. The friction coefficient of the ice surface cannot be effectively reduced if the concentration of the iodide ions is too low, and the freezing point of the solution will be lowered if the concentration of the iodide ions is too high, making the solution difficult to freeze.

In some embodiments, the anions in the salt solution are chlorate ions having a concentration that can be any value in a range from about 0.63 mmol/L to about 10 mmol/L, for example, 1.25 mmol/L, 2 mmol/L, 2.5 mmol/L, 3 mmol/L, 3.5 mmol/L, 4 mmol/L, 4.5 mmol/L, 5 mmol/L, 5.5 mmol/L, 6 mmol/L, 6.5 mmol/L, 7 mmol/L, 7.5 mmol/L, 8 mmol/L, 8.5 mmol/L, 9 mmol/L, 9.5 mmol/L, in an embodiment, about 1 mmol/L to about 5 mmol/L. The friction coefficient of the ice surface cannot be effectively reduced if the concentration of the chlorate ions is too low, and the freezing point of the solution will be lowered if the concentration of the chlorate ions is too high, making the solution difficult to freeze.

In some embodiments, the anions in the salt solution are perchlorate ions having a concentration that can be any value in a range from about 0.63 mmol/L to about 10 mmol/L, for example, 1.25 mmol/L, 2 mmol/L, 2.5 mmol/L, 3 mmol/L, 3.5 mmol/L, 4 mmol/L, 4.5 mmol/L, 5 mmol/L, 5.5 mmol/L, 6 mmol/L, 6.5 mmol/L, 7 mmol/L, 7.5 mmol/L, 8 mmol/L, 8.5 mmol/L, 9 mmol/L, 9.5 mmol/L, in an embodiment, about 1 mmol/L to about 4 mmol/L. The friction coefficient of the ice surface cannot be effectively reduced if the concentration of the perchlorate ions is too low, and the freezing point of the solution will be lowered if the concentration of the perchlorate ions is too high, making the solution difficult to freeze.

In some embodiments, the anions in the salt solution are thiocyanate ions having a concentration that can be any value in a range from about 0.63 mmol/L to about 10 mmol/L, for example, 1.25 mmol/L, 2 mmol/L, 2.5 mmol/L, 3 mmol/L, 3.5 mmol/L, 4 mmol/L, 4.5 mmol/L, 5 mmol/L, 5.5 mmol/L, 6 mmol/L, 6.5 mmol/L, 7 mmol/L, 7.5 mmol/L, 8 mmol/L, 8.5 mmol/L, 9 mmol/L, 9.5 mmol/L, in an embodiment, about 0.63 mmol/L to about 3 mmol/L. The friction coefficient of the ice surface cannot be effectively reduced if the concentration of the thiocyanate ions is too low, and the freezing point of the solution will be lowered if the concentration of the thiocyanate ions is too high, making the solution difficult to freeze.

The embodiments of the present disclosure will be further described in detail below with reference to specific examples. Further detailed description of the present disclosure is intended to help those skilled in the art and researchers to further understand the present disclosure. The relevant technical conditions and the like do not constitute any limitation to the present disclosure. Any modifications made within the scope of the claims of the present disclosure are within the protection scope of the claims of the present disclosure. The reagents and instruments used in the examples are known in the art unless otherwise specified. The experimental methods for which specific conditions are not indicated in the examples are realized according to conventional conditions, such as conditions described in literatures, books, or methods recommended by manufacturers.

Example 1

146.25 g of sodium chloride was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium chloride was 2.5 mmol/L, and a concentration of chloride ions was 2.5 mmol/L.

The ice-resurfacing truck sprayed the prepared ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 2

186.4 g of potassium chloride was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of potassium chloride was 2.5 mmol/L, and a concentration of chloride ions was 2.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 3

277.5 g of calcium chloride was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of calcium chloride was 2.5 mmol/L, and a concentration of chloride ions was 5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 4

405.5 g of ferric chloride was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of ferric chloride was 2.5 mmol/L, and a concentration of chloride ions was 7.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 5

585 g of sodium chloride was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium chloride was 10 mmol/L, and a concentration of chloride ions was 10 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 6

257.5 g of sodium bromide was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium bromide was 2.5 mmol/L, and a concentration of bromide ions was 2.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 7

515 g of sodium bromide was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium bromide was 5 mmol/L, and a concentration of bromide ions was 5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 8

618 g of sodium bromide was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium bromide was 6 mmol/L, and a concentration of bromide ions was 6 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 9

669.5 g of sodium bromide was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium bromide was 6.5 mmol/L, and a concentration of bromide ions was 6.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 10

375 g of sodium iodide was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium iodide was 2.5 mmol/L, and a concentration of iodide ions was 2.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 11

750 g of sodium iodide was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium iodide was 5 mmol/L, and a concentration of iodide ions was 5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 12

900 g of sodium iodide was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium iodide was 6 mmol/L, and a concentration of iodide ions was 6 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 13

212.5 g of sodium nitrate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium nitrate was 2.5 mmol/L, and a concentration of nitrate ions was 2.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 14

425 g of sodium nitrate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium nitrate was 5 mmol/L, and a concentration of nitrate ions was 5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 15

680 g of sodium nitrate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium nitrate was 8 mmol/L, and a concentration of nitrate ions was 8 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 16

850 g of sodium nitrate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium nitrate was 10 mmol/L, and a concentration of nitrate ions was 10 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 17

106.5 g of sodium chlorate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium chlorate was 1 mmol/L, and a concentration of chlorate ions was 1 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 18

266 g of sodium chlorate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium chlorate was 2.5 mmol/L, and a concentration of chlorate ions was 2.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 19

532 g of sodium chlorate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium chlorate was 5 mmol/L, and a concentration of chlorate ions was 5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 20

639 g of sodium chlorate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium chlorate was 6 mmol/L, and a concentration of chlorate ions was 6 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 21

122.5 g of sodium perchlorate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium perchlorate was 1 mmol/L, and a concentration of perchlorate ions was 1 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 22

306.1 g of sodium perchlorate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium perchlorate was 2.5 mmol/L, and a concentration of perchlorate ions was 2.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 23

490 g of sodium perchlorate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium perchlorate was 4 mmol/L, and a concentration of perchlorate ions was 4 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 24

612.2 g of sodium perchlorate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium perchlorate was 5 mmol/L, and a concentration of perchlorate ions was 5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 25

51 g of sodium thiocyanate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium thiocyanate was 0.63 mmol/L, and a concentration of thiocyanate ions was 0.63 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 26

121.5 g of sodium thiocyanate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium thiocyanate was 1.5 mmol/L, and a concentration of thiocyanate ions was 1.5 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 27

243 g of sodium thiocyanate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium thiocyanate was 3 mmol/L, and a concentration of thiocyanate ions was 3 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Example 28

324 g of sodium thiocyanate was weighed and added to a water tank of an ice-resurfacing truck, which has a volume of 1 m³. Water was added to fill the water tank and fully dissolve the salt, thus obtaining an ice-making solution. In the solution, a concentration of sodium thiocyanate was 4 mmol/L, and a concentration of thiocyanate ions was 4 mmol/L.

The ice-resurfacing truck sprayed the ice-making solution onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of ice-making solution was completely frozen, thus forming a new ice surface.

Comparative Example 1

Pure water was added to fill a water tank of an ice-resurfacing truck, which has a volume of 1 m³. The ice-resurfacing truck sprayed the water onto the original ice surface of an ice rink. The temperature of the ice surface was maintained at −7° C. After 30 minutes, the sprayed layer of water was completely frozen, thus forming a new ice surface.

Test Examples

The ice surfaces of the ice rinks made in Examples 1 to 28 and Comparative Example 1 and equal sized ice blocks frozen from the ice-making solutions and pure water were tested. The results are shown in Table 1 below. The test method was as follows:

1. Appearance of the ice rink was evaluated by visual inspection.

2. Crushing time: A MCR301 rheometer was used. The friction pair in the test consisted of a small ball with a diameter of 12.7 mm and the ice block to be tested placed under the small ball. The test was conducted under the following conditions: The pressure was 4.6 Mpa, the temperature was −7° C., and the line speed was 1.55 m/s. The small ball exerted pressure onto the ice block, and the cracking time of the ice block was tested.

3. Coefficient of friction: An ice surface friction test device was equipped with a three-component force sensor, under which was a pair of speed skating blades and above which was a 1500N load. The device slowly slid at a speed of 1 m/s on the ice surface of the ice rink to obtain the value of the friction force. The coefficient of friction was obtained by calculating a ratio of friction force to normal force. The test was conducted under the following conditions: The normal force was 1500N, the temperature was −7° C., and the line speed was 1 m/s.

TABLE 1 Coefficient Sample Appearance Cracking time of friction Example 1  Clean and intact More than 300 sec   0.0025 Example 2  Clean and intact More than 300 sec   0.0025 Example 3  Clean and intact More than 300 sec   0.0025 Example 4  Clean and intact More than 300 sec   0.0024 Example 5  Clean and intact More than 300 sec   0.0023 Example 6  Clean and intact More than 300 sec   0.0022 Example 7  Clean and intact More than 300 sec   0.0021 Example 8  Clean and intact More than 300 sec   0.0021 Example 9  Clean and intact More than 300 sec   0.0021 Example 10 Clean and intact More than 300 sec  0.002 Example 11 Clean and intact More than 300 sec  0.002 Example 12 Clean and intact More than 300 sec  0.002 Example 13 Clean and intact More than 300 sec  0.002 Example 14 Clean and intact More than 300 sec   0.0019 Example 15 Clean and intact More than 300 sec   0.0018 Example 16 Clean and intact More than 300 sec   0.0018 Example 17 Clean and intact More than 300 sec   0.0024 Example 18 Clean and intact More than 300 sec   0.0018 Example 19 Clean and intact More than 300 sec   0.0016 Example 20 Clean and intact More than 300 sec   0.0016 Example 21 Clean and intact More than 300 sec   0.0022 Example 22 Clean and intact More than 300 sec   0.0017 Example 23 Clean and intact More than 300 sec   0.0016 Example 24 Clean and intact More than 300 sec   0.0015 Example 25 Clean and intact More than 300 sec   0.0023 Example 26 Clean and intact More than 300 sec   0.0018 Example 27 Clean and intact More than 300 sec   0.0012 Example 28 Clean and intact More than 300 sec   0.0011 Comparative Micro-cracks 150 sec   0.0052 Example 1  on the surface

The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features are described in the embodiments. However, as long as there is no contradiction in the combination of these technical features, the combinations should be considered as in the scope of the present disclosure.

The above-described embodiments are only several implementations of the present disclosure, and the descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present disclosure. It should be understood by those of ordinary skill in the art that various modifications and improvements can be made without departing from the concept of the present disclosure, and all fall within the protection scope of the present disclosure. Therefore, the patent protection of the present disclosure shall be defined by the appended claims. 

What is claimed is:
 1. A method for making an ice surface of an ice rink, comprising: applying a salt solution to an ice surface, wherein the salt solution contains anions, and a concentration of the anions in the salt solution is in a range from about 0.63 mmol/L to about 10 mmol/L, the anions in the salt solution are selected from the group consisting of chloride ions, nitrate ions, bromide ions, iodide ions, chlorate ions, perchlorate ions, thiocyanate ions, and any combination thereof; and maintaining the ice surface at a temperature of about −4° C. to about 14° C. to naturally freeze the salt solution.
 2. The method according to claim 1, wherein the temperature of the ice surface is maintained at a temperature of about −6° C. to about −7° C. to naturally freeze the salt solution.
 3. The method according to claim 1, wherein the anions in the salt solution are chloride ions, a concentration of the chloride ions is in a range from about 2.5 mmol/L to about 10 mmol/L.
 4. The method according to claim 1, wherein the anions in the salt solution are nitrate ions, a concentration of the nitrate ions is in a range from about 2.5 mmol/L to about 8 mmol/L.
 5. The method according to claim 1, wherein the anions in the salt solution are bromide ions, a concentration of the bromide ions is in a range from about 2.5 mmol/L to about 6 mmol/L.
 6. The method according to claim 1, wherein the anions in the salt solution are iodide ions, a concentration of the iodide ions is in a range from about 2.5 mmol/L to about 5 mmol/L.
 7. The method according to claim 1, wherein the anions in the salt solution are chlorate ions, a concentration of the chlorate ions is in a range from about 1 mmol/L to about 5 mmol/L.
 8. The method according to claim 1, wherein the anions in the salt solution are perchlorate ions, a concentration of the perchlorate ions is in a range from about 1 mmol/L to about 4 mmol/L.
 9. The method according to claim 1, wherein the anions in the salt solution are thiocyanate ions, a concentration of the thiocyanate ions is in a range from about 0.63 mmol/L to about 3 mmol/L.
 10. An ice rink comprising an ice surface made by the method according to claim
 1. 